The present invention is directed toward a method and apparatus for adapting enlargers for use with large format negatives and more particularly to such a method and apparatus which can be employed with enlargers designed and built primarily for use with small format negatives.
Generally, commercially available enlargers which are portable or adapted for bench top operation are limited to use with small format negatives. Thus, amateur photographers or commercial photographers having limited darkroom space are precluded from enlarging large format negatives.
For purposes of the present invention, the term "large format" is intended to apply to negatives which are four inches by five inches and larger. Small format negatives are primarily contemplated as including 35 mm negatives, 21/4 inch negatives and four inch by five inch negatives at least under selected conditions. As for larger negatives included in the term "large format", eight inch by ten inch negatives and even negatives of larger size cannot be handled by presently available small format enlargers.
Many photographers using darkrooms of limited space (of the type referred to above) would prefer to be able to work with eight inch by ten inch or other large format negatives. A major advantage of course is that the large format negative has greatly increased surface area which permits much more subtle and detailed reproduction during enlargement. Although greater detail is possible with these large format negatives, commercially available large format enlargers are generally very expensive and require extensive amounts of space. For example, an enlarger capable of handling eight by ten inch negatives may cost as much as five to twenty times or more than commercially available bench top enlargers. In addition, existing large format enlargers may be as much as ten feet tall and weigh as much as 1,000 pounds. Accordingly, it is unrealistic for users of relatively small darkrooms to consider acquisition and use of these commercially available large format enlargers.
By way of example but without limiting the scope of the present invention in ay way, a typical small format enlarger of the type contemplated by the present invention is a Beseler enlarger (Model No. 45MX). The method and apparatus of the present invention is described below with particular exemplary reference to such an enlarger. The Beseler enlarger is described below only briefly in order to permit a complete understanding of the present invention. However, a greater understanding of the Beseler enlarger may be obtained for example by reference to U.S. Pat. No. 3,486,807 issued Dec. 30, 1969 under assignment to Charles Beseler Company. That patent relates to an enlarger (Beseler model CB7) which is of similar construction and operation as the above-noted Beseler model, at least for purposes of the present invention.
It is again emphasized that the method and apparatus of the present invention may similarly be employed with many existing small format enlargers (or even within an original enlarger design).
In any event, there has been found to remain a need for a method and apparatus for adapting such small format enlargers for use with large format negatives.